Importance of exercise, diet, eating habits, sleeping patterns

We have a 17 year-old daughter who suffers from bad, chronic migraines, and has for at least the last 2.5 years. She has had migraines for longer, but never as debilitating as they have been ever since I married her mom in Jul 2012. Her mom also suffers from migraines. Our daughter has also been diagnosed with major depressive disorder, anxiety, and ADHD combined type. She is a mess - not going to school, not contributing at home (e.g., no homework, no cleaning her room, leaving a mess wherever she goes), and not doing anything to help herself or the family. We have tried all sorts of treatments (e.g., nerve blocks, nasal (SPG) nerve blocks, biofeedback, chiropractor, accupunture, botox, ketamine infusions), tried all sorts of medications, have seen different neurologists, have been in pain clinics, and now we are looking into having neck/nerve surgery. With all that we have tried and done, I have been wondering about all the things in our control that our daughter has not been doing (that she is allowed to get away with not doing - that is another issue that I have been trying to address with my wife, which is beyond the scope of my posting here in this forum), namely exercise (none), diet (high carb/sugar/starch, minimal vegetables, lack of water (mostly drinks cans of Sprite), lots of fast food/snacks), eating habits (erratic/undisciplined - misses meals, eats a small meal then snacks later, not uncommon to eat very early then return to bed or sleep watching TV, not uncommon to eat late at night), and sleep patterns (erratic/ undisciplined - no set times for sleep and getting up, not uncommon to sleep most of the day). I call exercise, diet, eating habits, and sleep patterns "EDES" for short. How important are those things to managing migraines? Our daughter has heard from professionals many times the value/benefit of those things, yet she (and my wife) continue to focus on treatments and medications. I know those things will make for a stronger and healthier body that can augment the treatments and medications, and help minimize the frequency, intensity, and duration of her migraines. I am hoping others will have some personal insights about EDES that I may be able to share with my wife and daughter. I know I would be doing everything I could within my control to fight migraines, but I am at a loss when it comes to motivating our daughter to do the same, and getting my wife to not accept our daughter's lack of effort and self-discipline.